Heat-insulating container and apparatus for producing the same

Abstract

A heat-insulating container is used for an instant dried food and is excellent in heat-insulating property, design and economy. The container comprises a paper cup body with a bottom, which has an inner surface coated with a polyolefin resin and is provided with an outward curled portion formed at an upper opening end of the cup body and at least one horizontal rib formed on a side wall of the cup body so as to project outward therefrom; and an inverse-frustoconical paper sleeve provided with an inward curled portion formed at a lower end of the sleeve. The cup body and the sleeve are integrally combined with each other so that an upper end of the sleeve is joined to an outer periphery of the side wall of the cup body, which is adjacent to the outward curled portion of the cup body, and an inner surface of the inward curled portion of the sleeve is joined to an outer periphery of a lower portion of the side wall of the cup body.

The invention claimed is: 
     
       1. A sleeve forming apparatus for forming a sheet-like blank into a sleeve used as an outer package of a heat-insulating container, comprising:
 a mandrel having a body portion which is capable of being fitted inside the sleeve and which is shorter than the sleeve; 
 a curling device for curling up a blank on the mandrel in such a manner that one end portion of the blank to which an adhesive agent is applied is located under another end portion of the blank to form a joint line; 
 a main-sealing device for pressing the joint line onto the mandrel; 
 an assist-sealing device for nipping one end portion of the joint line, which projects from the mandrel by a pair of nippers; 
 an end-curling device for pressing a projecting portion of the blank, which projects from the mandrel, toward the mandrel to form a curled portion of the sleeve; and 
 a sleeve-ejecting device for removing the sleeve from the mandrel. 
 
     
     
       2. A sleeve forming apparatus according to  claim 1 , further comprising a blank-supplying device for supplying the blank to the curling device with applying the adhesive agent to the one end of the blank. 
     
     
       3. A sleeve forming apparatus according to  claim 1 , further comprising:
 a conveyor capable of circulating along a predetermined circulation path and having mandrel-attachment portions arranged along the circulation path with leaving a certain interval therebetween, each of the attachment portions being provided with the mandrel; and 
 a driving device for moving the conveyor intermittently by a pitch corresponding to the interval between the mandrel-attachment portions to feed the mandrel on each of the mandrel-attachment portions step by step with respect to a plurality of stations defined along the circulation path; 
 wherein the curling device, the assist-sealing device, the end-curling device and the sleeve-ejecting device are distributed to the stations in such a manner that the mandrel is fed to the curling device, the assist-sealing device, the end-curling device and the sleeve-ejecting in this described order in accordance with movements of the conveyor. 
 
     
     
       4. A sleeve forming apparatus according to  claim 3 , wherein the main-sealing device is movable along the circulation path together with the mandrel. 
     
     
       5. A sleeve forming apparatus for forming a sheet-like blank into a sleeve used as an outer package of a heat-insulating container, comprising:
 a conveyor capable of circulating along a predetermined circulation path; a plurality of mandrels arranged on the conveyor so as to leave a certain interval therebetween in a circulation direction of the conveyor; 
 a driving device for moving the conveyor intermittently by a pitch corresponding to the interval between the mandrels to feed each of the mandrel step by step with respect to stations defined along the circulation path; 
 a blank-supplying device for supplying the blank to a curling station selected from the stations with applying an adhesive agent to one end portion of the blank; 
 a curling device for curling up the supplied blank on each of the mandrels in such a manner that said one end portion of the blank is located under another end portion thereof to form a joint line; 
 a sealing device for pressing both end portions of the blank, which forms the joint line, to each other; and 
 a sleeve-ejecting device provided in an ejecting station which is selected from the stations and is located forward from the curling station in the circulation direction for removing the sleeve from each of the mandrels; 
 wherein each of the mandrels has a body portion which is capable of being fitted inside the sleeve and which is shorter than the sleeve, and wherein the sealing device comprises a main-sealing device for Dressing the joint line of the blank to each of the mandrels and an assist-sealing device for nipping one end portion of the joint line, which projects from each of the mandrels, by a pair of nippers. 
 
     
     
       6. A sleeve forming apparatus according to  claim 5 , wherein the assist-sealing device is provided in an assist-sealing station selected from the stations and located between the curling station and the ejecting station. 
     
     
       7. A sleeve forming apparatus according to  claim 6 , wherein an end-curling device for processing an curled portion on a projecting portion of the blank, which projects from each of the mandrels, is provided in at least one end-curling station selected from the stations and located between the assist-sealing station and the ejecting station. 
     
     
       8. A sleeve forming apparatus according to  claim 3  or  7 , wherein the stations include at least two end-curling stations, each of which is provided with the end-curling device. 
     
     
       9. A sleeve forming apparatus according to  claim 3  or  5 , wherein the conveyor comprises a turn table capable of turning about a predetermined axis. 
     
     
       10. A sleeve forming apparatus according to  claim 1  or  5 , wherein the sleeve-ejecting device removes the sleeve from each of the mandrels by pressing a roller onto the sleeve fitted on each mandrel with rotating the roller about an axis perpendicular to an axis of each mandrel.